Thanks for your reply.
The video player has Blu-ray capability and the TV is Full HD, It plays hi-res MP4 files magnificently.
I played the DVD I made on my computer as you suggested and the result is the same. Tomorrow I will try the MP4 file and see how it is but I think it will be fine.
Looking at the video it seems the problem is that it is a little jerky. PAL is only 25 FPS but I don't think that is the full story.
I am wondering if I should be setting the bit rate in some way, checking the box to use the internal codec (I don't even know what codec it is using, or checking either or both of the boxes for two pass encoding and interlaced video.
I'm running out of DVDs so any advice would be welcome.